England in the 70's

I need help with a few questions. I’ve done the basic Google searches, and I’ve also searched this comm, and didn’t find exactly what I wanted.

My story is set in England, summer of ’76. Four 16 year olds take a road trip from Northampton to Liverpool.

Question 1: How long would that trip take? I found this site which says about three hours, and I was wondering if that’s accurate, and if it’s accurate for the 70’s. Seems an awfully short trip (and then I’d have to have some sort of mishap that would make it longer).

Question 2: What kind of car would they have? The car belongs to one of the boys’ mother, who is a History teacher. I want something that’s cheap but reliable. I was thinking of a Beetle, they were very popular and cheap here in Brazil, but I have no idea if they would be good for a story set in England.

Question 3: When they get to Liverpool, they obviously find some accommodations. Would they be asked for id’s to prove they’re of age? Is it realistic enough that they find a place that doesn’t ask (i.e., somewhere dodgy where the owner doesn’t care who comes and goes)?

Question 4: There’s a scene in my story where they are asked by a group of girls to a party in a someone’s house. In my head, is this big party like the ones in movies, with teenagers drinking and dancing and having sex in spare rooms. Is this accurate for the place and time?

Thanks in advance.

EDIT : I totally forgot to mention that the one doing the driving has a fake driver's license, since he is only a few months short of 17. I was just wondering if the other boys would need some sort of fake id too.